CELLS TO BODY SYSTEMS UNIT REVIEW

By Mrs. Susan Dennison2012-13

What are cells?Cells are the basic units of structure and function of all living things. They are also called the “building blocks” of life.

What is an organism? An organism is a living thing made up of one or more cells, each able to support the functions (jobs) of life.

We should addhere that anothermust-have characteristicis to be made up of 1 or more cells!

How many cells make up certain types of organisms?

The simplest organisms, such as bacteria or an amoeba, are each a single cell. However, most plants and animals are made of many cells. Humans, for example, are made up of trillions of cells! Each cell has a particular function (job).

What determines the size and shape of a cell?

The size and shape of a cell depend on its function. For example, red blood cells are small and disc-shaped so they can fit through blood vessels. Muscle cells are long and thin because they need to contract and stretch.

Who “discovered” cells?Several scientists made important observations and conclusion about cells.

Theodore Schwann, a German zoologist, concluded that all animals are made of cells.

Robert Hooke recorded his observations of cork cells in 1665. He coined the term “cell” while working in England.

Matthias Schleiden, a German botanist, concluded that all plants are made of cells.

How do scientists view cells?Scientists view microbes and cells with a microscope. Dutch scientist, Anton Van Leeuwenhoek, is considered the “Father of Microbiology” because the important advances he made to the design of microscopes.

What are the parts of a cell?Each cell has even smaller structures inside, called organelles. Each organelle has a particular job, or function, in the life processes of a cell.

Are plant and animal cells different? Yes! Two organelles (smaller structures inside

cells) that only plant cells have are cells walls and chloroplasts.

Which organelles do I need to know about this year, in 5th grade?

Plant Cells Animal Cells1. Nucleus 1. Nucleus2. Chromosomes 2. Chromosomes3. Cell Wall 3. Cell Membrane4. Cell Membrane 4. Cytoplasm5. Cytoplasm 5. Vacuoles6. Chloroplasts 6. mitochondria7. Vacuole8. Mitochondria

What is the nucleus?The nucleus is the organelle that controls all of a plant or animal cell’s activities and the production of new cells.

Here, you can seeThe nucleus in humancheek cells, just like youdid in your 2nd class lab!

What are chromosomes?Chromosomes are threadlike structures that contain information about the characteristics of the plant or animal, like eye color, flower color, shape, etc.

What is a cell membrane?The cell membrane is a covering that holds the plant or animal cell together and separates it from its surroundings.

When you think about a membrane, imagine it is like a big plastic bag with some tiny holes. That bag holds all of the cell pieces and fluids inside the cell and keeps other things outside the cell. The holes are there to let some things move in and out of the cell in a process called osmosis.

What is a cell wall?Only plant cells have cell walls! They are rigid layers that support and protects plant cells.

What is cytoplasm ?Cytoplasm is a jellylike substance that contains many chemicals to keep the cell functioning.

What are chloroplasts?Chloroplasts are organelles that help make food for the plant cell during photosynthesis. Only plant cells need them, so only plant cells have them!

What are vacuoles?

Vacuoles in plant and animal cells are organelles that store food, water, and waste.

What are mitochondria?Mitochondria are organelles in plant and animal cells that release energy from food.

How do materials move in and out of a cell?

Cells need to get needed materials like food, water, and oxygen. They also need to get rid of wastes, like carbon dioxide. Materials move in and out of cells by a process called diffusion.

What is osmosis?Osmosis is the movement of water and dissolved materials in and out of a cell through a cell membrane.

Normal onion cells plumpedUp with water and cytoplasmInside the cell membrane

Onion cells that have less water in them-the cytoplasmhas started to shrink.

Can I see osmosis?In a way, you see it all of the time! Not at a cellular level, though. By drinking, animals replace the water their cells lose. By soaking up rain in the soil, water moves back into the plant’s cells.

How are our bodies organized?Cells work together to make tissues. Tissues work together to form organs. Organs work together to form organ systems.

What are examples of cells?

Plants and animals have many types of cells, including: skin cells, muscle cells, blood cells, stem cells, etc.

What are examples of tissues?

• Muscle tissue- made up of cells that contract and relax to move your skeleton

• Nervous tissue- made up of cells that get signals from the brain to hear, see, taste, touch, and smell

• Connective tissue- made up of cells that are in bones, cartilage, and tendons

• Epithelial tissue- made up of cells that cover the body of an animal and make the lining of most internal organs

What are examples of organs?

Organs are layers of tissue. Each organ in an animal’s body performs a certain function that keeps the animal alive. Examples include the: heart, lungs, kidneys, gallbladders, etc.

STUDY YOUR SCIENCE NOTES!

There will be more information tested. You have a variety of notes, diagrams, and information in your science notebooks to use for this content. Hopefully, you’ve been studying all along and don’t have to cram!